body
{
  width: 800px;
}

div#header
{
  height: 100px;
  width: 100%;
  background-color: #ccc;
}

div#footer
{
  height: 100px;
  width: 100%;
  background-color: #ccc;
}

div#main
{
  width: 100%;
  height: 400px;
}

div.column
{
  float: left;
  height: 100%;
}

div#main div.column:nth-child(1),
div#main div.column:nth-child(3)
{
  width: 20%;
}

div#main div.column:nth-child(2)
{
  width: 60%;
}

div#left
{
  background-color: #fcc;
}

div#middle
{
  background-color: #cfc;
}

div#right
{
  background-color: #ccf;
}

div.nav
{
  border: 3px solid black;
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
  -webkit-border-radius: 4px;
  -moz-border-radius: 4px;
}

div#navs
{
  height: 400px;
}